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Messages - Josh

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Amateur Radio / Re: Unknown Ale Frequencies
« on: January 13, 2022, 0539 UTC »

Equipment / Re: Can a common mode choke really help reduce RFI?
« on: January 11, 2022, 2300 UTC »
If there's no choke at the feedpoint the line IS participating in reception and reception pattern, in the case of a tx in transmission. Then again anything conductive attached to the feedpoint, often a mast or ground wire, is too. This reception includes household noise from inside the house and near field picked up by the line and fed to the antenna and thus back down to your rx. As for reception pattern, no choke at the feed of a horizontal diploe means the feed is adding vertical polarisation to the erstwhile horizontal polarised antenna. The problem is if it's a conductor it's an antenna, and antennas typically only send down the feedline about 1/3rd the rf they pick out of the aether and reradiate the rest back into the aether. Shame of it all. Yes 1/3rd is all you get.

edit; (haha I was wrong here, you get 2/3rds of the received signal, not 1/3rd you big dummy, but that 1/3rd is still getting away)

For example of feedline effect, the tiny pa0rdt active antenna types typically show much more "gain" when grounded to a metal pole above ground than just hanging off a choked feedline, this reveals the nature of what's going on - the pole and/or line's doing most of the receiving.

Software / Re: SDR Console
« on: January 11, 2022, 2247 UTC »
Console has been my goto sdr app for rsps and the like for a few years now. The stability, simplicity, and low cpu use over sdruno and several other sdr apps I tried is a big seller. Next is HDSDR, no one beats HDSDR for low cpu and mem footprint in my testing but HDSDR doesn't do vrx so for vrx work console it is.

Shortwave Pirate / Re: UNID 6925 USB 2135 UTC 11 JAN 2022
« on: January 11, 2022, 2242 UTC »
ALERT! Whistling and olas @ 2237Z

I am prepared to receive your transmission!

Equipment / Re: 4:1 or 1:1 ? Neither?
« on: January 11, 2022, 2238 UTC »
If you will be using the dipole for the freq of resonance, a 1:1 will divorce the feed line from the reception pattern nicely and may provide best transfer of energy, the z the antenna sees is also nominal to the feed line. In the case where a dipole is used at freqs outside of resonance, where the z seen by the wire is very different from the z of the feed, over or under coupling might transfer more received energy and this will be freq/wire length dependent.

Odd 1/4 frequency multiples of antenna wire length should result in low feedpoint z meaning a good match for direct coax feed, evens over a halfwave should result in much higher z. A halfwave endfed has around 2k ohm z.

Shortwave Pirate / Re: UNID 6925 USB 2135 UTC 11 JAN 2022
« on: January 11, 2022, 2225 UTC »
OM ranting jba @ 2223Z

Shortwave Broadcast / RHC 11760 2215Z 11DEC22
« on: January 11, 2022, 2223 UTC »
RHC 11760 2215Z 11DEC22
Rousing speech from Dan Ortega of Nicaragua into solo by yl.
-81dBm sigs

ai yi yi!

Weather / Re: Good and cheap wx station?
« on: January 11, 2022, 2109 UTC »
Excellent, thank you for the input!

Pirate Radio History / Re: Radio Metallica history website
« on: January 11, 2022, 2108 UTC »
Wow those guys were nuts!

Shortwave Pirate / Re: UNID 6925 AM 2043 UTC 11 Jan 2022
« on: January 11, 2022, 2100 UTC »
Trace of carrier @ 2057 in southern IN.

10/11 meters / Re: N4PAL/B 28.214 10 JAN 2022
« on: January 11, 2022, 2057 UTC »
28.2082  WN2A/AK2F  C BUDD LAKE/RANDOLPH, NJ   #  4W, VERTICAL (alternating ID)
coming in well here atm, several others in view on panadaptor.


10/11 meters / Re: Late night "E" on 10M to 06:00UTC!
« on: January 11, 2022, 2043 UTC »
Tis the season for sporads of e methinks.

Utility / Re: CIS Navy on HF
« on: January 10, 2022, 2014 UTC »
T-600 599 8345 Washington D.C. HEAVY volume of traffic. 0830z.

I've only seen them run it on 8345 once and that was only heard by the most sensitive rig here, nice catch.

Utility / Re: UNID(s) 11689 1835 UTC USB/AM 2 Jan 2022
« on: January 10, 2022, 2010 UTC »
I've caught US/NATO mil fsk sigs in the hfbc band on occasion, with broadcasters firing up on an ongoing fsk sig and vice versa.

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